Fitting wrench



June 3, 1969 LENNQN ET AL 3,447,405

FITTING WRENCH Filed Sept. 28, 1967 FRED A LE-I RI K J 36 F|G.5 EMERY J. ZAHURANEC,

ZOLTAN SZOHATZKY 8 EDWARD BECK ATTORNEYS United States Patent 3,447,405 FITTING WRENCH Fred A. Lennon, Chagrin Falls, Emery J. Zahuranec, Solon, Zoltan Szohatsky, Mentor Township, Lake County, and Edward Beck, Cleveland Heights, Ohio, assignors to Crawford Fitting Company, Solon, Ohio, a corporation of Ohio Filed Sept. 28, 1967, Ser. No. 671,333 Int. C]. 1325]) 13/02 US. Cl. 81-119 6 Claims ABSTRACT OF THE DISCLOSURE A wrench having a handle with a head positioned at least at one end thereof. The head is provided with a set of jaws opening laterally of the wrench handle and providing substantially parallel jaw faces. The geometric center of each jaw face falls on a line generally perpendicular to the plane of the face and passing approximately through the geometric center of the remaining face and of the handle.

Background of the invention This invention relates to a wrench especially adapted for gripping the bodies of fittings used in fluid conduit systems.

More particularly, the present invention is generally designed to be used with what is commonly known as a T fitting. It is also quite useful with elbow fittings. In the case of the Tfitting, the coupling body is branched to provide a single inlet and dual outlets, or vice versa. The elbow fitting, on the other hand, is generally L- shaped, with an inlet at the free end of one leg, and an outlet at the free end of the other. In either event, connection means are provided for attaching fiuid' conduits to the branches of the fitting (or legs, as'the case may be), and each such means is ordinarily actuated by a coupling nut. The present wrench is particularly useful in threading and unthreading the coupling nut on the central branch of the body, or on either leg of the elbow fitting.

In this connection, when torque is applied to the coupling nut on the central branch of the T or on one of the legs of the elbow, forces are generated which tend to turn and twist the fitting. In cases where the remaining branches of the fitting have already been attached to fluid conduits, such as tubing for example, a danger exists that the tubing may be bent or otherwise damaged, or that the seals between fitting and tubing may be disrupted.

In order to hold the fitting properly so that no distortion of the tubing occurs, a Wrench of some sort is ordinarily employed. The wrench usually has jaws which grasp the center of the coupling body between the two branches which are on a common axis. This point will also be on the axis of the central stem of the T, or in the case of the elbow, on the axis of one leg. In other words, the wrench grasps the coupling body at the intersection of the axes of the several branches or legs of the fitting.

Because it is the purpose of the wrench to prevent 'ice the coupling body from turning or rotating, it can be appreciated that the handle of the wrench should be perpendicular to the plane of the fitting. This allows the maximum utilization of force for holding the coupling body, in that all components of force in other directions will be eliminated. This position is further advantageous in that the handle of the wrench will then lie in a plane parallel to the plane in which a second wrench will travel when used to tighten or loosen the coupling nut on the central branch of the fitting.

Another characteristic of the ideal fitting wrench is that the handle should be positioned with respect to the jaws such that during use for the intended purpose no rotational forces are created about the longitudinal axis of the wrench handle. These forces or moments tend to twist the handle in the users hand, and inhibit proper tightening of the coupling nut.

Summary of the invention;

Wrenches embodying the present invention specifically meet the objectives previously outlined. That is, the wrench handle has been designed so that the zone at which the handle of the wrench is grasped by the user will be generally about a line perpendicular to the plane of the fitting and of the jaw faces. This line also passes through the geometric center of each jaw face, through approximately the center of the handle, and, on application of the wrench to the fitting, generally through the center of the coupling body.

One embodiment of the present device has a set of jaws at but one end of the wrench. The second embodiment of the present invention has a set of jaws provided at each end of the wrench.

In the dual head embodiment of the wrench, the jaws open in opposite directions and laterally of the wrench. Both sets of jaws are also generally parallel to one another and at an acute angle to the longitudinal axis of the handle. This relationship between the handle and the jaws is a result of designing the wrench so that the geometric center of each jaw face lies on a line passing through the geometric center of each remaining jaw face and through the center of the handle. The same is also generally true of the single head version of the invention, except, of course, that the line passes through the center of the wrench handle and but one set of jaw faces.

This design helps to eliminate extraneous forces and particularly moments of rotation about the central or longitudinal axis of the wrench handle. Thus, when the jaws of the wrench grasp the coupling body and the coupling nut of the central branch of the fitting is tightened, there will be virtually no tendency of the handle to rotate in the users hand about its own longitudinal axis.

It is contemplated that for some applications it may be desirable to provide one or more of the jaw faces with detent means to aid in the securement of the fitting on the wrench. Such means are not, however, considered essential to the basic concept of the invention.

Description of the drawing FIG. 1 shows a single jaw version of the present invention in side elevation and in use with a fitting shown in phantom outline;

FIG. 2 is a fragmentary top view of the wrench in use with a fitting shown in phantom outline;

FIG. 3 is a fragmentary side view, in section and enlarged scale, of a form of the invention using detent means provided in one jaw face;

FIG. 4 is a side elevational view of a dual jaw version of a wrench embodying the present invention; and

FIG. 5 is a top view of the wrench illustrated in FIG. 4.

Description of the preferred embodiments FIG. 1 illustrates a single head fitting wrench The wrench 10 has a handle 11 and a head 12. The handle 11 generally has a narrow neck portion 13 which gradually widens in a direction away from the head 12 until end 14 is reached. Handle \11 is so shaped to maximize convenience in grasping the wrench and to distribute the weight of the wrench more evenly along its length.

The head 12 has jaws 14a providing faces 15 which are used to grasp a T fitting generally illustrated in phantom outline at 16. Faces 15 are connected by a bottom surface 15a.

A coupling nut 18 is positioned on the central branch 19 of the T fitting 16. The coupling nut 18 is grasped by a conventional wrench 21 which is situated for tightening or loosening such nut. Tubing 22 is illustrated extending from the central branch 19 of the T fitting 16.

As seen in FIGS. 1 and 2, a line perpendicular to the plane of the fitting and passing through its center extends through the geometric center of each jaw face 15 and is perpendicular to the plane of each such face. Further, such line passes approximately through the center of the handle.

Moreover, as best seen in FIG. 2, the head 12 of the wrench '10 grasps the coupling body 23 such that the central axis of the tubing 22 passes approximately through the geometric center of bottom surface 15a.

It can be seen that as the wrench 21 turns the coupling nut 18, forces will be generated tending to turn the fitting 16 about the central axis of tubing 22. Such turning, it not inhibited, may well cause damage to the connections of the fitting with tubing 27 and 28. However, in the present case, the fitting wrench 10 secures the body of the coupling so that this will not occur. Moreover, because of the particular design of the present wrench, a second phenomenon is also prevented. This is the tendency of the handle 11 to rotate about its own longitudinal axis when the jaws are not acting in a plane which passes through the handle. Such tendency, if not overcome, makes it considerably more difiicult properly to secure T fittings in fluid line systems. As previously explained, the present wrench is so constructed as to permit a straight line to pass perpendicular to the jaw faces of the wrench through their geometric centers and through approximately the center of the handle in the grasp region, thus reducing the rotational force or moment M to zero about the longitudinal axis of the handle.

As best shown in FIG. 3, it is sometimes useful to provide one or more of the jaw faces with suitable detent means 17. The detent may include a spring 29 biasing a ball bearing 30 which abuts against the circumference of an opening 32 which has a diameter slightly smaller than the diameter of the ball bearing 30, thus to retain the ball in position.

FIG. 4 illustrates a second embodiment of the present invention wherein two sets of jaws 33 and 34 are provided, one set in each of the heads 36 and 37. The jaws in one head may be sized differently than those of the other, if desired, in order to permit the wrench to accommodate a different size fitting at each end. Detents 38 and 39 may be provided in one or more faces of jaw sets 33 and 34, respectively. Handle 41 connects the heads 36 and 37, and has its longitudinal axis positioned at an angle somewhat less than 90 to the planes of the jaw faces, the latter of which are generally parallel to one another. As was the case in connection with the embodiment of FIGS. 1 and 2, the geometric center of each jaw face falls on a line which passes through the geometric center of the handle 41, the geometric center of such remaining jaw face, and which is generally perpendicular to such faces.

Use of the specific relationship discussed above permits a fitting to be grasped by either of the sets of jaws such that the effective point about which the handle is secured to the fitting lies on a line which passes through the geometric center of the handle. Moreover, this line is perpendicular to the plane of the fitting and passes through the center of the fitting. This relationship virtually eliminates components of force which tend to rotate the handle in the hand of the operator, and thus permits tightening of the coupling nut on the lateral branch of the fitting with a facility not present in the prior art.

The foregoing description is not intended to limit the invention beyond the scope of the appended claims.

We claim:

1. A wrench particularly adapted for use with a T type fitting having at least one nut-actuated coupling device, said wrench comprising:

a handle;

a head at one end of said handle, the entire head being relatively thick in comparison to its height;

a set of jaws protruding into and extending the entire thickness of said head, said jaws opening laterally to one side of said head and providing a pair of jaw faces whereby said jaw may grasp the body of the fitting and withstand substantial torques about an axis parallel to the jaw faces;

a substantially fiat bottom surface at the inner ends of the jaw faces to allow a fiat bottom of the fitting to seat securely thereon;

the geometric center of each jaw face falling on a line generally perpendicular to the plane of such face, and passing through the geometric center of the remaining face and approximately through the center of the handle of said wrench;

said line further lying in a plane generally parallel to the plane of rotation of the nut used in actuating the coupling device of the fitting.

2. The wrench of claim 1 wherein a detent is positioned in at least one of the jaw faces to aid in grasping said fitting.

3. The wrench of claim 2 wherein said detent comprises a spring biased ball.

4. A wrench for securing a fitting such that a coupling nut on the fitting may be rotated without causing substantial rotational moments about the axis of the wrench, said wrench comprising:

a handle;

heads at either end of said handle, the entire heads being relatively thick in comparison to their height;

a set of jaws protruding into and extending the entire thickness of each said head, said sets of jaws opening in opposite directions from one another and providing jaw faces generally parallel to one another so that said jaws may grasp the body of a fitting and withstand substantial torques about an axis parallel to the jaw faces;

a substantially flat bottom surface at the inner ends of each set of jaw faces to allow a flat bottom of the fitting to seat securely thereon;

the plane of each said jaw face intersecting the longitudinal axis of said handle at an angle less than the geometric center of each said jaw face lying on a line generally perpendicular to said face, and passing approximately through the geometric center of each remaining face and of said handle.

5. The wrench of claim 4 wherein detent means is provided in the jaw faces of said wrench.

6. The wrench of claim 5 wherein each detent comprises a spring biased ball.

References Cited UNITED STATES PATENTS 216,690 6/1879 Mikkelson 81-119 X 463,044 '11/1891 Hammack 81-119 X 916,951 3/1909 Jefirey 811 19 X 6 1,168,204 1/ 1916 Helstrom. 2,800,816 7/1957 Tasciotti 81-125 X FOREIGN PATENTS Ad. 13,266 1916 Great Britain.

95,067 11/ 1923 Austria.

MILTON S. MEHR, Primary Examiner. 

